Burton w



B. W. SWEET.

ELECTRIC SWITCH.

APPvucATLoN FILED MAR. 2. |916.

Pateutede; 30,191.9. l

TURNEY.

'y UNITED 'STATES PATENT oEEiCE.

BURTON W. SWEET, OF CLEVELAND, OHIO, ASSIGNOR TO ,THE VAN DORN ELECTRIC TOOL COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

Specification of Letters Patent.

ELECTRIC SWITCH. v

Application filed March 2, 1916. Serial No. 81,701.

To all 'whom z' may/concern:

Be it known that I, BURTON W. SWEET, a citizen of the United States of America, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented 4certain new and useful Improvements in Electric Switches, of which the following is a specification.

-My invention relates to improvements in electrical switches, and has for its object the provision of a switching device which is eiiicient, durable and snappy in operation.

The essential features of my invention comprise a circuit controlling element and a plunger or push-button mechanism cooperating. therewith.

The circuit controlling element carries a circuit closer which engages contacts in order to close electrical circuits for lighting systems, motors-or the like.

The circuit controlling element `or member is provided with two wedge shaped or conical surfaces which are adapted to be engaged by roller Ibearings associated with and cont-rolled by the plunger mechanism. AThese bearings are mounted within a suitable case and are encircled by a spiral spring which is of proper tension to insure sufficient presure of the bearings against the tapering or conical surfaces of the circuit closing element to cause Vits movement.

When one of the conical surfaces is engaged by the roller bearings the circuit closing element is caused to move in one. -direction to close the switch contacts and when the other conical surface is engaged theelement moves in the opposite direction and opens the -switch contacts. Y

By the use of roller bearings the friction is reduced to a minimum and all chance of `possible binding or sticking removed.

' low.

My invention is illustrated in the accompanying drawings wherein:

Figure l is a plan View of the assembled switch with the 4cover remo-ved.

Fig. 2 isa side view in section on the line 2-2. y v

Fig. 3 is an endview in section on the line 4C is a side view partly in section.

Fig. 5 is an end view in section on the l-ine 5-5.

Fig. 6 is an end View in section on the line 6 6.

Fig. 7 is a side view in section of the roller bearing case. l

Fig. 8 is an end view in section of the rol-ler bearing case. i I

Referring first to Figs. 1 and 2, the switch mechanism proper 4is shown mounted withinl the case a. This case is provided with a screws c. When the cover is in place it serves to -bind or hold in position the insulating terminal block g, the bushing Zi and the latch bar j. By removing lthe cover the entire mechanism can be lifted from the case.

The bushing Zi through which the plunger d passes is provided with a recessed portion h1 which fits snugly within a eut-out portion of the case a. The case a is also provided with cut-away portions in which the block g lits, as indicatedv in Figs. 1 and 6.

The-plunger d is of insulating material, fiber or preferably of hard rubber. As shown in Fig. 2, the reduced 4portion of this plunger passes through the bushing Z9 and is provided with an enlarged portion at d2. A section of this enlarged portion is surrounded by a metallic rino Z3 whichis forced thereon. This metallic ring forms a bearing surface foi the latch bar y'. `The end Patented. Dec. 30, 1919. v

cover c, fastened to the case by means of the through the .insulating terminal block g.

This bushing g3 is of metal so as to present a suitable bearing surface for the portion 11.3 of the circuit controlling element. The opening in the case e and in the enlarged portion'of the plunger d permits free movement of the cone portion of the element It."

The plunger (Z is kept in the position shown in Figs. 'l and 2 by means of the spring f. This spring encircles the portion c* of the case e and also the extended portion of the bushing g3.

By referring particularly to Figs. 2, et and 8 it will bel noted that the roller bearings e2 fit within the openings e made within the recessed portion of the case e. Surrounding these roller bearings isla spiral spring e3 which serves to hold the bearings in place and to force them against the conical surfaces h and Il?. The tension of this spring is such that when the bearings engage the conical surfaces the element 7L is forced in a direction depending upon' which conical surface is engaged.

Attached to one end of the element It is a metallic disk or circuit closer'z', preferably made of copper. This disk is fitted over the reduced portion h5 after which a collar L is forced on the reduced portion and riveted thereto to hold the washer z' in lace.

The disk z' is itted loosely upon the reduced portion h5 so as to allow it to tilt slightly in all directions. This arrangement makes the disk self adjusting in relation to the contacts g1 and g2 in order to compensate for wearingof the parts.

Vhen the plunger l is 'depressed the disk i engages and short circuits the two terminals g1 and g2 which are mounted upon they insulating terminal block. To allow connections to be made to these two terminals by the wires or conductors the screws and clips as shown at g4 and g5 are provided. These screws and clips are in electrical engagementv or contact with their respective terminals g2 and g1.

Referring particularlyV to Figs. 3 and 5 the arrangement wherein the plunger is held in a locked position is shown. The latch bar y' passes through the case a as shown. One end of this bar is provided with a rounded reduced portion jl. Encircling this reduced portion is a spring jz which bears against the enlarged portion of the latch y' and against the inner side of the case ab. This spring serves to force the latch bar j outward so the end jl will project from thev case a. This latch bar is cut away, as shown at js.A The cut-away portion conforms to the surface of the ring cl3, which is forced over the enlarged portion of the plunger cl. The portion 7'3 is cut away in this manner to allow the ring cl3 to move back and forth under the latch bar y'.

l/Vhen the plunger d is in its outward or normal'position, as shown in Figs. 1 and 2,

the inner surface of the cut-away portion je' of the latch y' rests upon the periphery of the ring d3. When the plunger Z is inits depressed position, as shown in Fig. 4, the enlarged portion of the latch y' passes benezaeie tween the shoulder b3 of the bushing I) and the sleeve or ring (Z3, as shown in Figs. 'Jr

I and 5.

The operation of the device 'is as fol-` lows: p

In Figs. l and 2 the switch is shown in its normal position; in other words, the terminals 'g1 and g2 are not short circuited by the disk or washer z'. In order to complete the circuit between g1 and g2, the `plunger (Z is depressed. The depression of 4this plunger causes the separat-ion of the ride upon the conical surface It of the cir.

cuit controlling element h. As soon as these roller bearings pass over the ridge formed by the intersection ofthe two conicall surfaces tl and h2 then the roller bearings will engage the conical surface h2. The pressure exerted by the spring e3 causes the roller bearings to press against and force the circuit controlling element in the position shown in Fig. Ll; namely, with the.

disk z' engaging the two terminals g1 and g2.

It willbe noted that the pressure exerted upon the two terminals g1 and g2 by the disk z' is controlled entirely by thepressure ofthe roller bearings e2 upon the conical surface h2, dueto the pressure exerted by the spring e?. rThe plunger mechanism is.

controlled by exerting pressure -upon the plunger (Z and simply forcesthe roller bearing -case e to a certain position whereupon the circuit controlling element is `quickly and automatically caused to assume the position shown in Fig. 4 with the disk 'Il engaging the terminals g1 and g2.

ln order to open the circuit or sever the connection between terminals g1L and g2,

pressure is exerted upon the projecting end Y jl ofthe latch bar j thereby causing the cut-away portion ja to come in alinement with the surface of the ring cl3. As soon as the two surfaces come in alinement the plunger al and the roller bearing case e are restored to the positions shown in Figs. l and 2, vdue to the tension exerted by the spring f. During this restoration of the plunger, the roller bearings e2 are forced over the conical surface 71,2 until the conical surface h1 is engaged whereupon the device z, is forced into the position shown in Figs. land 2 by means of the pressure ex-` erted by the rollers e2 upon the conical surface 71,1. stored to its normal position, the cut-away portion of the latch j rests upon the ring d.

After the mechanism is fully rey From the foregoing description it will be seen that the circuitcontrolling element it is independent or automatic in its action.

' vice h. after which by its independent movement quickly opens or closesy the circuit between the terminals g1 and g2.

The roller bearings c2 insure positive action and with little Wear.

quick and The circuit controlling element L is free to ro-.

tate within its bearings and the plunger l vwith its mechanism is also free to rotate thus allowing a natural and uniform wear on all of the cooperating parts.

It will befunderstood that either ball or suitable roller bearings may be interposed between the inclined faces 0f the cones andV the 'concentric spring; said elements serving to relieve the spring from torsional vor rotating strains, which would tend to break the spring if said elements Were not provided. moditied in the details set forth, without departing from the spirit of my invention.

Having thus described my inve-ntion what I desire to secure by Letters Patent isi.

il. In a device 0f the class described, the combination with a movable circuit closer provided with conical surfaces, of contacts; adapted to be engaged by said circuit closer, depressible plunger mechanism prpvided with roller bearings, means for operating said plunger mechanism whereby said bearings engage one of said conical surfaces andcauses said lcircuit closer to engage said contacts, a latch bar for holding said plunger mechanism in a depressed position, means for returning plunger mechanism to its normal position, means for operatingsaid latch bar to cause the restoration of said plunger mechanism, said plunger mechanism in restoring causing .said roller bearings to engage another of said conical surfaces there by disengaging said circuit closer from said contacts, substantially as set forth.

2. In a device of the class described, the

Also, the structure described may be combination with a movable circuit closing element provided with two conical surfaces, of contacts adapted to be engaged by said circuit closing element, depressible plunger mechanism provided with'y roller bearings, means for depressing said plunger mechanism whereby said bearings engage one of-said conical surfaces to move said` circuit closer into engagement with said contacts, a latch bar for holding said plungermechanism in its depressed position, restoring means .for said plunger mechanism, means for operatving said latch bar to render said restoring means effective whereby the plunger mechanism in returning to its normal position causes the roller bearings to engage the other of said conical surfaces to throw the circuit closer out of engagement with said contacts, substantially as set-forth.

'8. yThe combination of a movable circuit closing element, a movable plunger mechanism in which the circuit closingelement is movably received, conical surfaces formed lger and in position to ride upon said surfaces when the said plunger moves in either direction, a springnormally holding said plunger at the limit of. its movement in one direction, and a latch bar to hold said plunger against the tension of said spring.

In testimony whereof I do now affix my signature in the presence of two Witnesses.

BURTON W. SWEET. p

|Witnesses:

FRANK BUBUA, ALBERT LYNN LAWRENCE. 

